Head covering assembly with face and visor seals



P 1954 R. s. COLLEY 3,149,632

HEAD COVERING ASSEMBLY WITH FACE AND VISQR SEALS Filed Feb. 1, 1961 IN VEN TOR. RUSSELL S. COLLEY Bi 6, 7 1% Mo? ATTi'.

United States Patent 3,149,632 HEAD CQ'VERHNG ASflEMBLY WlTl-i FACE AND VISGR SEALS Russell S. Qoliey, (Zuyahoga Falis, (Ohio, assignor to The B. F. Goodrich Company, New York, N.Y., a corporation of New Yuri;

Filed Feb. 1, 1961,8212 No. 86,433 Claims. (Cl. 128142) The invention relates to head coverings for enclosing the entire head of the wearer and especially to head covering assemblies including face and visor seals for use with flying suits.

Heretofore, head coverings including transparent visors used with flying suits and adapted to be under internal pressure, have had air-impervious face seal-s which caused undue perspiring of the wearers skin contacting the face seal, and which generally fitted the face contour unsatisfactorily. This produced objectionable discomfort of the wearer and defective sealing against the face. One of the principal objects of the invention is to provide an improved head covering assembly with transparent visor wherein the discomfort of the face seal due to perspiration is effectively reduced or eliminated, and wherein an effective face seal and visor seal are assured and maintained.

According to the invention, the head covering assembly comprises a helmet with a face opening, a flexible impervious diaphragm peripherally secured to the helmet adjacent the face opening and defining a face seal opening, a flexible endless sealing band including venting means supported by the diaphragm andextending around the face seal opening for contacting and conformance with the wearers face, and means in communication with the venting means of said band for conducting air under pressure thereto.

In a preferred form of the invention, the helmet is of rigid fire-proof, impact-resistant material and the diaphragm is of fabric reinforced elastomeric sheet material. The sealing band may be backed by a frame member around the face seal opening and may have a plurality of superposed layers one of which is flexible cellular material with an open-:cell structure positionable adjacent the wearers face and underlying another layer of flexible cellular material of closed-cell structure. The sealing band may also have endless passage means in communication with the open-cell layer formed of an impervious flexible fabric secured to the back of the closedcell layer along a readward zone thereof and to the opencell layer along a narrow front zone thereof constituting a seal area of the band.

I One embodiments of the invention has a fixedly mounted transparent visor closing the face opening in sealed relation around margin thereof, a non-inflatable sealing member contacting the visor and said margin of the helmet face opening. A modified embodiment of the invention includes a pivotally mounted transparent visor and an improved endless inflatable sealing'member about the helmet face opening adapted to contact the visor in the closed position thereof, when the member is inflated.

In the accompanying drawings which constitute a part of this specification and in which like numerals are employed throughout to designate like parts,

FIG. 1 is a side elevational view of a head covering assembly connected to an inflatable flying suit and con structed in accordance with and embodying the invention, parts being broken away;

FIG. 2 is a front elevational view of FIG. 1 showing the head covering assembly and flying suit;

FIG. 3 is a cross-sectional view in an enlarged scale taken along line 3 3 of FIG. 1, parts being broken away Patented Sept. 22., 1964 and a dot and dash curved line indicating a side of the wearers face;

FIG. 4 is a fragmentary side elevational view of a modi fied construction of the head covering assembly shown in FIG. 1 with a pivotally mounted visor and inflatable seal therefor, and

FIG. 5 is a cross-sectional view in an enlarged scale taken along line 55 of FIG. 4, parts being broken away.

The particular construction shown in FIGS. 1, 2 and 3 includes a helmet 10 formed of rigid fire-proof, impactresistant material such, for example, as a plasticized epoxy resin reinforced with fiberglass material, which helmet may be of domed or other suitable configuration adapted to enclose the head and adjacent neck portion of the wearer in spaced relation thereto. The helmet 10 may be detachably connected to an impervious flexible neck portion 11 of an inflatable flying suit by a separable rotatable bearing connector 12, one bearing ring of which is fixedly united with the helmet and the other bearing ring with the neck portion 11. The arrangement facilitates unlimited rotation of the helmet 10 relative to the neck portion 11, and also convenient attachment and detachment of the helmet to the suit. However, the details of the construction and arrangement of the connector 12 constitute no part of the invention.

The rigid helmet 10 at the front thereof has a face opening, indicated by the numeral 13, to accommodate the wearers face, which face opening is approximately circular in front elevation and generally concave in side elevation. A rigid visor 14 of suitable transparent plastic material closes the face opening 13 and has a rounded configuration adapted to substantially conform to the contour of the face opening margin and of the domed configuration of the helmet. As shown in FIGS. 1 and 3, the visor is fixedly mounted adhesively in sealing relation to margin of the helmet 10 about the face opening 13 by a non-inflatable sealing element or member 15 of elastomeric material; but in the modified embodiment shown in FIGS. 4 and 5 the visor 14a is pivotally mounted by means 37 on opposite sides of the helmet 10a and disposed in contact with an inflated sealing element or member 15a adhesively secured to the margin of the helmet 10a around the face opening 13a. The modified construction described more fully hereinafter permits swinging the visor 14a from a position in front of the Wearers face to a position at the top of the helmet, when the sealing element 15a is deflated and the wearer is on the ground or is flying at a safe altitude such, for example, as below 12,000 feet where extra oxygen for breathing is not required.

An endless small diameter tube 16 with integral attaching flange is adhesively secured to the'helmet at the inner surface thereof as shown in FIGS. 1, 2' and 3, and extends about the face opening 13 with a series of peripherally spaced, small diameter apertures 17 through the wall of the tube. The endless tube 16 is of oxygenresistant, flexible synthetic rubber composition such as plasticized polyvinyl chloride and is adapted to conduct oxygen under pressure received from an oxygen demand regulator valve 19. When the wearer inhales, the regulator valve opens whereby a jet of oxygen issues from each of the apertures 17 about the entire periphery of the face opening 13; but when the wearer exhales, the regulator valve 19 automatically cuts off the oxygen sup ply to the tube 16. The apertures in the tube are aligned and arranged to direct the jets of oxygen radially inward across the adjacent inner surface of the visor 14, thereby preventing fogging of the visor by the condensation of the moisture in the exhaled breath. The oxygen is normally inhaled by the wearer when flying at altitudes above about 12,000 feet with the helmet 10 attached to the flying suit and with the visor 14 in the closed position as shown in FIGS. 1, 2 and 3.

Conduit means 18 which may be a flexible oxygenresistant synthetic rubber hose, is connected to the endless tube 16 in communication therewith and extends rearwardly therefrom within the helmet to and in communication with the oxygen demand regulator valve 19 which has an on-oif control button 19a. The oxygen demanded regulator valve has a part thereof mounted at the interior and a second part thereof mounted at the exterior of the helmet and is connected by a suitable hose 18a to an external source of oxygen under rela-- tively high pressure. However, the valve 19 construction itself is known and constitutes no part of the invention. When the button 1% is in the on position, oxygen is admitted to the valve 19, but when in the off position, oxygen to the valve 19 is cut-off.

The invention provides a flexible, impervious diaphragm 2b peripherally secured air-tight, preferably adhesively, to the helmet 1t) adjacent the face opening 13 and defining a face seal opening 21 of generally oval configuration in front elevation as shown in FIG. 2, and generally concave configuration in side elevation as shown in FIG. 1. The diaphragm 2t provides with the helmet and the visor 14 an oral-nasal-ocular cavity indicated by the numeral 22, and the inner part of the valve 19 is located in this cavity. The oxygen under pressure flowing through the apertures 17 of the endless tube 15, when the wearer inhales, provides an internal pressure within the cavity 22 substantially greater (for example, about 1 /2 p.s.i. absolute) than the internal pressure (for example, about 3.6 p.s.i. absolute.) of the air within the helmet space rearwardly of the diaphragm 20, which helmet air pressure is substantially the. same as that of the inflating air within the torso of the flying suit. This pressure differential at the two sides of the diaphragm 2d facilitates an effective face seal.

The flexible impervious diaphragm 2t is made of elastomeric material such as natural or synthetic rubber or other rubber-like or elastomeric material having substantially similar chemical composition or physical properties to natural rubber and to equivalents therefor, and capable of undergoing, under appropriate influences such as heat, pressure and the action of a chemical substance, a change from an essentially plastic flowable condition to a relatively firmer or harder, more elastic and resilient condition. The elastomeric material of the diaphragm is reinforced with preferably an elastically stretchable fabric which may be formed of textured yarns or filamentary elements so woven or knitted as to provide stretchability longitudinally, laterally and diagonally of the fabric in sheet form, a textured yarn being one in which the fiber or fibers making up the yarn have been mechanically distorted from their usual straight-line or their low-order helical formation about the central axis of the yarn.

Preferably, the fabric reinforcement is a tubular knit fabric of continuous filament, stretch yarn of thermoplastic material such, for example, as nylon (a polyamide of adipic acid and hexamethylene diamine). and is known commercially as Helanca fabric. The stretch yarn consists of multi-filament nylon subjected to at least the three, per se known, basic steps of first high twisting, then heat setting, and next untwisting or relaxing, whereby a crimp is heat set into the yarn which crimp consists of irregular, randomly set curls or waves. The effect is that the yarn, when relaxed, has a memory and will resume its twisted, contracted state. The Helanca knitted nylon fabric suitably coated or otherwise treated with the elastomeric material for imperviousness, is arranged in the diaphragm Ztl so that it is elastically stretchable in all directions with slightly greater stretchability in the direction laterally of the diaphragm.

The diaphragm 2% despite its stretchability characteristics actually limits the movement of the wearers head Al. Within the helmet lit, and also compels rotation of the helmet it? on hearing connector 12 when the wearer turns his head, thus providing for mobility of the head. However, slight movements of the head are accommodated by the stretchable diaphragm 20 without rotation of the helmet 143.

The diaphragm Zil is provided with coil spring-actuated check valve means 23 of known construction which means is in the open condition, when the wearer exhales, and is in communication with the helmet space rearwardly i.e., back of the diaph agm. The check Valve means 23 is closed when the wearer inhales, but during exhalation permits exhausting the moisture-laden breath of the wearer from the cavity 22 to such helmet space and thence to the interior of the flying suit from which it is subsequently exhausted to the atmosphere in a known manner. The means 23 facilitates maintaining the greater internal pressure in the cavity 22, than that in the helmet space rearwardly of the diaphragm.

A frame member 24 of rigid strip metal or plastic may be pre-formed to shape and secured to the marginal edge of the diaphragm Ztl around the face seal opening 21. The frame member is desirably of a soft aluminum alloy whereby it can be bent subsequently to fit more precisely the contour of the particular wearers face. The frame member 24 is endless and like the face seal opening 21 is concave in side elevation and generally oval in front elevation, and is so shaped and proportioned as to pass across the forehead and rearwardly down along the temples, forwardly and downwardly across the cheeks and thence across the front of the chin below the lips of the wearer, as shown especially in FIGS. land 2.

The rigid frame member 2d is adhesively secured to the diaphragm Ztl by a V-shaped in crosssection, peripherally-extending, air-impervious fabric tape 25 with one leg of the V-shaped tape adhered to the radially outer surface of the frame member 24 and with the other leg of the if-shaped tape adhered to the adjacent surface of the diaphragm 2%, as shown especially in FIG. 3. The construction advantageously provides a hinged attachment of the frame member to the diaphragm.

A flexible endless sealing band 25 is secured to the radially inner surface of the frame member 24 around the face seal opening 21 for conformance with the wearers face. In the preferred construction shown especially in FIG. 3, the sealing band 26 has its inner surface consisting of an air-pervious fabric 27 for contacting the skin of the wearers face. The fabric 27 is adhered throughout to one side of a peripherally continuous ventting layer 23 of yieldable material with passages therethrough such, for example, as elastomeric cellular material with an open-cell structure to conduct venting air through the layer to the helmet space rearwardly of the diaphragm.

The air-pervious fabric27 may be a fabric of continuous filament yarn of wool, silk, cotton, rayon or nylon material knitted or so woven as to resemble knitting, whereby the fabric (known commercially as tricot) is substantially inextensible longitudinally but highly stretchable laterally, i.e., substantially inextensible in the direction along the wales but highly stretchable in the direction along the courses of the knitted fabric. The preferred tricot fabric is formed of nylon continuous filament yarn suitably pro-shrunk to stabilize the fabric and prevent further shrinkage during cure of a suitable rubber cement which adheres the fabric to the venting layer 28. The tricot fabric 27 arranged to be substantially inextensible circumferentially of the sealing band, permits the passage of perspiration from the wearers face through the interstices in the fabric to the cellular material of the venting layer 28. The venting air in its passage through the layer 28 picks up and transmits the perspiration to the rearward helmet space back of the diaphragm 29 and at the same time effects a definite evaporative cooling of the wearers skin in contact with the sealing band.

The venting layer 28 may, if desired, have adhered to its other side an endless strip 27a of tricot knitted nylon fabric. Suitable rubber cement securely adheres a peripherally continuous, impervious, support layer 29 to the layer 28. The support layer 29 is of yieldable impervious material such, for example, as elastomeric cellular material with a closed-cell structure and is disposed in superposed backing relation to the venting layer 28. The support layer 29 may be relatively thicker than the venting layer 28 to provide improved cushioning and support of the venting layer 28. The tricot knitted fabrics 27, 27a are so arranged that they are substantially inextensible peripherally but stretchable laterally of the sealing band to facilitate a good fit of the said band in conformance to the contour of the wearers face.

The sealing band 26 also includes endless passage means 30 around the face seal opening 21 in peripherally continuous communication with the venting layer 28 for conducting thereto venting air which is at a pressure slightly greater than that in the rearward helmet space. The endless passage means 3t) for the particular construction shown especially in FIG. 3 is formed of an endless strip of Helanca knitted nylon fabric coated with suitable elastomeric material to render the strip air-impervious. The endless fabric strip St is adhered at its rearward marginal'portion to the radially outer side of the impervious support layer 29 and then extends forwardly in unattached spaced relation to the layer 29 and to the front marginal edges of the respective layers 28, 29, and is adhered at its front marginal portion in overlapping sealing relation to the air-pervious fabric 27 and the venting layer 28. This arrangement of the endless fabric strip 30 provides space for the flow of venting air peripherally around the front of the sealing band 26 and into and rearwardly through the venting layer 27.

The air-impervious support layer 22 at its front marginal portion has a plurality of peripherally space-apart slots 31 extending diagonally across the corner in the manner shown especially in FIG. 3, thereby assuring the flow of venting air to the venting layer. The intervening portion of the endless fabric strip 30 adjacent the frame member 24 is adhesively secured peripherally around and entirely across the frame member 24 in the manner shown in FIG. 3, thus attaching the sealing band to the frame member. The impervious front marginal portion of the endless fabric strip 30 adhered to the air-pervious fabric 27 and venting layer 28 at the front of sealing band is of substantially lesser width as indicated by the letter A, than the overall width of the sealing band so that the major portion of the width of the fabric 27 is available for the passage of perspiration and air. The peripherally continuous, relatively narrow, impervious front marginal portion of the strip 30 constitutes the principal sealing area (at A) of the sealing band. The pressure of the venting air in means 35) acting on the layers 28, 29 facilitates an effective seal at such area A of the sealing band. The discomfort of the sealing band is thereby greatly reduced because the major portion of its width can be util ized to cool the skin of the wearer.

i The frame member 24 has extending through an aperture therein a headed tubular screw 32 secured in place by means of suitable hexagonal nut 33, the tubular screw also extending through an opening in the fabric wall of the passage means 30 with the screw head at the interior of the passage means. The screw 32 has a short, bent tubular extension 34 which is attached to a flexible rubber hose 35 adapted, to be connected to a source of venting airunder pressure, which source is external of the torso of the suit. There is provided a shallow, narrow groove 36 extending diametrically entirely across the screw head in communication with the circular central opening therein so as to prevent sealing the central opening in the head of the screw 32 by the layer29. The venting airpressure is slightly greater (about 0.5 p.s.i. absolute) than that in figuration with greater width than thickness.

the rearward helmet space and hence that within the torso of the flying suit, so as to overcome the low resistance of the cellular material of the venting layer 28 to the flow of the air therethrough laterally of the sealing band 26.

When the wearer has the flying suit on with the helmet connected thereto and-enclosing his head in the manner shown in FIGS. 1 and 2, and the control button 19a of the oxygen demand regulator valve 19 is in the on position, the sealing band 26 around the face seal opening 21 conforms to and contacts the face of the wearer with the narrow sealing area A at the front marginal region of the band thereby effectively preventing the flow of oxygen and of exhaled breath from the oral-nasal-ocular cavity 22 past the face seal into the rearward helmet space. Such sealing makes possible maintaining the relatively greater internal pressure in the cavity, while the oxygen is being admitted into the cavity 22 by the endless tube 16 only when the wearer inhales, and while the oxygen is cut-off and the exhaled breath is being exhausted through the check valve means 23. The said internal pressure in the cavity 22 produces tautness in the diaphragm 20 so that the latter, by virtue of its attachment to the helmet 10, compels rotation of the helmet 19 relative to the neck portion 11 of the suit, when the wearer turns his head. The venting air under pressure flows continuously through the tubular screw 32 into the endless passage means 30 of the sealing band 26 and then lateral- 1y through the venting layer 28 to the rear margin of the sealing band and thence into the rearward helmet space. During the flow of the venting air through passages in the venting layer 28, the air picks up moisture from the air-pervious fabric 27 contacting the skin of the wearer rearwardly of the sealing area and thus evaporatively cools the skin of the wearers face so that the wearer suffers little discomfort from perspiration during extended use of the flying suit.

The modified construction of the head covering assembly shown in FIGS. 4 and 5 differs from the assembly construction shown in FIGS. 1, 2 and 3 in that a transparent plastic visor 14a of segmental rounded shape is pivotally mounted on a rigid domed helmet 10a by transversely aligned mounting means 37, 3'] located at opposite sides of the helmet 18a. This permits the visor 14a to be swung about the axis of said means 37 to its lower position to cover a face opening 13a in the helmet 10a as shown in FIG. 4, and to be swung to its upper position at the top of the helmet 10a to fully open the face opening 13a. The visor 14a has its rounded inner surface in spaced substantially parallel relation to the adjacent rounded outer surface of the helmet 10a in both the lower and the upper positions.

Inflatable means 15a is provided to seal in an air-tight manner the space between the margin of the face opening 13a and the visor 14a when the latter is at the lower position, and thereby coact with the visor 14a, and with the diaphragm 20, check valve means 23 and sealing band 26 which are included in said modified construction in providing the oral-nasal-ocular cavity 22a adapted to be maintained under internal pressure. The modified construction, like the construction shown in FIGS. 1, 2 and 3, includes the endless tube 16 with apertures 17 suitably secured to the inner surface of the helmet 10a about the faceopeni ng 13a and connected by conduit means 18 to that part of the oxygen demand regulator valve 19 within the cavity 22a. v

The inflatable means 15a is preferably an endless inflatable sealing element or member of fiat cross-sectional con- The sealing member 15a extends around the face opening 13a in adhesively secured relation to the outer surface of the helmet 10a at the margin of the face opening. As shown in FIGS. 4 and 5, the endless sealing member 11a is inflated outwardly and contactsthe adjacent inner surface of the vi-sor 14a in sealing relation thereto.

The inflation of the sealing member 15a is accomaraaaaa F? 4 plished by a suitable synthetic rubber hose38 in communication with the sealing member 15:: and connected to said part of the oxygen demand regulator valve 19 Within the vacity 22a in a manner such that relatively high pressure oxygen is admitted to the sealing member 15a while the control button 1% is in the on position, but is cut off while the control button 19a is in the off position. This facilitates rapidly inflating the sealing member when the visor 14a is in the lower position, and subsequently deflating the sealing member 15a by exhausting the contained oxygen through the valve w to the cavity 225: before the visor 14a is swung to the upper position. The sealing member 1511 elastically retracts and resumes its fiat configuration While the oxygen is being so exhausted.

The sealing member 15a is of elastomeric material such, for example, as neoprene (a polymer of chloroprene, namely, Z-chlorobutadiene) having embedded therein a reinforcement 39 of bias-cut woven nylon fabric. The fabric reinforced neoprene elastomeric material is constructed and arranged to form an endles tube which, in the uninflated condition, has flat inner and outer wall portions substantially in contact and has integral portions 49, 41 constituting an attaching base underlying the centrally divided inner wall portion of the tube. The attaching portions 4%, 41 are adhered to the helmet lilo around the face opening 13a. A reinforcing tape 42 of suitable fabric reinforced neoprene elastomeric material within the tube is adhered to the divided inner wall porton and spans the divide therein to close the same.

When the sealing member 15a is uninflated, there is clearance between its flat outer wall portion and the visor 14a to permit swinging the visor down to its lower position in overlapping relation to the sealing member, and to permit swinging the visor 14:: up to its upper position. This clearance is eliminated and the outer Wall portion of the sealing member 15a contacts and firmly presses outwardly against the visor 14a in air-tight sealing relation, when the sealing member is inflated as shown in FIG. 5.

' In the operation of the modified head covering assembly, assuming the wearer has donned the helmet we: and has the sealing band as conforming to and contacting his face, the visor 14a is swung downward from its upper position to its lower position as shown in FIG. 4. When this lower position is reached, the wearer pushes the control button 1% to the on position, whereby the inflowing oxygen at relatively high pressure passes through the valve 19, the rubber hose 38 and into the sealing member 15a thereby substantially simultaneously inflating the same entirely around the face opening 13a. The inflation compels the outer wall portion of the sealing member 15a to contact and firmly pres-s outwardly against the adjacent inner surface of the visor 14a thereby effecting the improved face opening seal. The sealing member 15a remains continuously inflated so long as the control button 19a is in the on position.

The oxygen under relatively lesser pressure for breathing purposes is conducted from the valve 19 through the rubber hose 18 to the endless tube 16 and thence in the form of jets out through the apertures 17 into the cavity 22a, each time the wearer inhales. When the wearer exhales, the oxygen supply to the endless tube 16 is automatically cut off by the valve 19 and the moisture-laden exhaled breath within the oral-nasal cavity 22a is exhausted through the check valve means 23 to the helmet space rearwardly of the diaphragm 2i The pivotal mounting arrangement of the visor 14a advantageously permits removal of the latter from in front of the wearers face, when the wearer is flying at a safe altitude. To this end, the wearer pushes the control button 19a to the off position thereby stopping the supply of oxygen to the endless tube 16 and to the sealing member 15a. This deflates the sealing member 15a which elastically resumes its initial flat configuration whereupon there is clearance between the sealing member 15 and the visor 14a so that the visor can be swung upwardly to its upper position.

Variations may be made without departing from the scope of the invention as defined in the following claims.

I claim:

1. A head covering assembly comprising a helmet having a face opening in the front thereof, a transparent closure for said opening, a flexible impervious diaphragm extending about the periphery of said opeiing with its outcr periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening, and a flexible endless sealing band supported by and joined in air-tight relation to said diaphragm and extending around said face seal opening for contact and conformance with the wearers face, said sealing band being provided with passages for conducting air therethrough in contact with the wearers face, and means including at least one conduit in communication with the passages in said sealing band for conducting air under pressure thereto and means for supplying the helmet wearer with a breathable gas.

2. A head covering assembly comprising a helmet having a face opening in the front thereof, a transparent clo sure for said opening, a flexible impervious diaphragm extending about the periphery of said opening with its outer periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening, and a flexible endless sealing band supported by and joined in air-tight relation to said diaphragm and extending around said face seal opening for contact and conformance with the wearers' face, said sealing band including peripherally continuous venting means having a layer of yieldable material with passages for conducting air therethrough in contact with the wearers face to the helmet space rearwardly of said diaphragm, means in veluding at least one conduit in communication with said venting means for conducting air under pressure thereto, and means for supplying the helmet wearer with a breath able gas and for exhausting the exhaled air from the helmet assembly.

3. A head covering assembly adapted to be under internal pressure comprising a helmet having a face opening in the front thereof, a transparent visor mounted on said helmet closing said face opening, a flexible impervious diaphragm extending about the periphery of said opening with its outer periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening and providing with said helmet and visor an oral-nasal-ocular cavity, a rigid frame member secured to said diaphragm around said face opening, a flexible endless sealing band secured to said frame member around said face seal opening for contact and conformance with the wearers face, said sealing band comprising venting means including flexible cellular material with an open-cell structure to conduct venting air under pressure to the helmet space rearwardly of said diaphragm and positionable adjacent the wearers face, an air-impervious flexible support layer backing and united with said venting layer, and endless passage means around said sealing band in communication with said venting layer for conducting thereto the said venting air, and conduit means connected to said passage means for supplying thereto the said venting air under a pressure greater than that in the said helmet space, and means for introducing a breathable gas into said cavity and for exhausting the exhaled air from the said cavity.

4. A head covering assembly adapted to be under internal pressure comprising a rigid helmet having a face opening in the front thereof, a rigid transparent visor mounted on said helmet closing said face opening, a flexible impervious diaphragm extending about the periphery of said opening with its outer periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening and providing with said helmet and visor an oral-nasal-ocular cavity, a rigid frame member secured to the marginal edge of said diaphragm around said face seal opening, a flexible endless sealing band secured to said frame memher around said face seal opening for contact and conformance with the wearers face, said sealing band comprising venting means including a layer of flexible cellular material with an open-cell structure to conduct venting air under pressure through said layer to the helmet space rearwardly of said diaphragm and presenting an 'air-pervious surface positionable adjacent the wearers face, an air-impervious flexible elastomeric support layer backing and united with said venting layer, and endless passage means around said sealing band in communication with the venting layer for conducting thereto the said venting air, and conduit means connectedto said passage means for supplying thereto the said venting air under a pressure greater than that in the said helmet space, means for introducing into and exhaustinga breathable gas from said cavity. 7

5. A head covering assembly adapted to be under internal pressure comprising a rigid helmet of domed configuration having a face opening in the front thereof, a rigid transparent visor of rounded configuration mounted on said helmet closing said face opening, an endless tube extending about said face opening with a series of peripherally spaced small apertures through the wall of the tube, conduit means connected to said tube for conducting oxygen under pressure thereto, a flexible impervious diaphragm peripherally secured to said helmet adjacent said face opening and defining a face seal opening and providing with said helmet and visor an oralnasal-ocular cavity, check valve means on said diaphragm for maintaining the internal pressure in said cavity greater than that in the helmet space rearwardly of the diaphragm, a rigid frame member secured to said diaphragm around said face seal opening, a flexible endless sealing band secured to said frame member around said face seal opening for contact and conformance with the Wearers face, said sealing band comprising a peripherally continuous venting layer of elastomeric cellular material with an open-cell structure positionable adjacent the Wearers face and adapted to conduct venting air under pressure through said layer to the said helmet space, a pcripherally continuous support layer of elastomeric cellular material with a closed-cell structure backing and united with said venting layer, and endless passage means around said sealing band in communication with said venting layer for conducting thereto the said venting air, and conduit means connected to said passage means for supplying thereto the said venting air under a pressure greater than that in said helment space.

6. A head covering assembly adapted to be under internal pressure comprising a rigid helmet of domed con figuration having a face opening in the front thereof, a rigid transparent visor of rounded configuration mounted on said helmet closing said face opening, an endless tube extending about said face opening with a series of peripherally spaced small apertures through the wall of the tube, conduit means connected to said tube for conducting oxygen under pressure thereto, a flexible impervious diaphragm peripherally secured to said helmet adjacent said face opening and defining a face seal opening and providing with said helmet and visor an oral-nasal-ocular cavity, check valve means on said diaphragm for maintaining the internal pressure in said cavity greater than that in the helmet space rearwardly of the diaphragm, a rigid frame member secured to the marginal edge of said diaphragm around said face seal opening, a flexible endless sealing band secured to said frame member around said face seal opening for contact and conformance with the wearers face, said sealing band comprising an airpervious fabric for contacting the skin of the wearers face adhered to a peripherally continuous venting layer of elastomeric cellular material with an open-cell structure to conduct venting air under pressure through said layer to the said helmet space, a peripherally continuous support layer of elastomeric cellular material with a closedcell structure backing and adhered to said venting layer, and endless passage means around said sealing band in peripherally continuous communication with said venting layer for conducting thereto the said venting air, and contube, conduit means connected to said tube for conducting oxygen under pressure thereto, a flexible impervious diaphragm of resilient rubbery material with an elastically stretchable fabric reinforcement therein peripherally secured to said helmet adjacent said face opening and defining a face seal opening and providing with said helmet and visor an oral-nasal-ocular cavity, check valve means on said diaphragm for maintaining the internal pressure in said cavity greater than that in the helmet space rearwardly of the diaphragm, a rigid frame member secured to the marginal edge of said diaphragm around said face seal opening, a flexible endless sealing band secured to said frame member around said face seal open ing for conformance with the wearers face, said sealing band comprising an air-pervious fabric for contacting the skin of the wearers face adhered throughout to a peripherally continuous venting layer of resilient rubbery cellular material with an open-cell structure to conduct venting air under pressure through said layer to the said helmet space, a peripherally continuous support layer of resilient rubbery cellular material with a closed-cell structure backing and adhered throughout to said venting layer, and endless passage means secured to said frame member and extending around said sealing band in peripherally continuous communication with said venting layer for conducting thereto the said venting air, and conduit means mounted on said frame member and connected to said passage means for supplying thereto the said venting air under a pressure greater than that in said helmet space.

8. A head covering assembly comprising a helmet with a a face opening in the front thereof, a transparent visor adapted to cover said face opening when at its lower position, means pivo'tally mounting said visor on the helmet with its inner surface spaced from the outer surface of the helmet, an endless inflatable sealing member of elastomeric material and flat cross-sectional configuration mounted on said outer surface of the helmet around said face opening, said sealing member in the inflated condition contacting said inner surface of said visor in sealing relation thereto when the visor is at said lower position, means carried by said helmet in communication with said sealing member to conduct inflating fluid under pressure thereto, an endless tube mounted on the inner surface of the helmet and extending about said face opening with a series of peripherally spaced small apertures through the wall of the tube, conduit means connected to said tube for conducting oxygen under pressure thereto, a flexible impervious diaphragm extending about the periphery of said face opening with its outer periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening and providing with said helmet and visor an oral-nasal-ocular cavity, and flexible endless sealing band means including venting means comprising flexible cellular material wi'th an open cell structure supported by said diaphragm and extending around said face seal opening for contact and conformance with the wearers face, and conduit means in communication 1 i with said venting means to conduct venting fluid thereto, and means to exhaust exhaled air from said cavity.

9. A head covering assembly comprising a rigid helmet with a face opening in the front thereof, a rigid transparent visor pivotally mounted on the helmet with its inner surface spaced from the outer surface of the helmet and adapted to cover said face opening when at its lower position, an endless inflatable sealing member of flat crosssectional configuration mounted on said outer surface of the rigid helmet around said face opening, said sealing member in the inflated condition'contaeting said inner surface of said rigid visor in sealing relation thereto when the visor is at said lower position, means carried by said helmet in communication with said sealing member to conduct inflating fluid under pressure thereto, a flexible impervious diaphragm extending about the periphery of said opening with its outer periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening, flexible endless sealing band means supported by and joined in air-tight relation to said diaphragm and extending around said face seal opening for contact and conformance with the wearers face, means for supplying the helmet wearer with oxygen, and means for exhausting the exhaled air.

10. A head covering assembly comprising a rigid helmet with a face opening in the front thereof, a rigid transparent visor pivotally mounted on the helmet with its inner surface spaced from the outer surface of the helmet and adapted to cover said face opening when at its lower position, an endless inflatable sealing member of fabricreinforced elastorneric material and fiat cross-sectional configuration with greater width than thickness mounted on said outer surface of the rigid helmet around said face opening, said sealing member in the inflated condition having a flat outer wall portion thereof contacting said inner surface of said rigid visor in sealing relation thereto when the visor is at said lower position, means carried by said helmet in communication with said sealing member toconduct inflating fluid under pressure thereto, a flexible impervious diaphragm extending about the periphery of said opening with its outer periphery secured to said helmet adjacent said face opening and with its inner periphery defining a face seal opening, and flexible endless sealing band means supported by and joined in air-tight relation to said diaphragm and extending around said face seal opening for contact and conformance with the wearers face, and means for supplying the helmet wearer with oxygen and for exhausting the exhaled air.

References Cited in the file of this patent UNITED STATES PATENTS 2,861,568 Quilter et al. Nov. 25, 1958 I 2,882,896 Seeler Apr. 21, 1959 FOREIGN PATENTS 815,499 Great Britain June 24, 1959 

1. A HEAD COVERING ASSEMBLY COMPRISING A HELMET HAVING A FACE OPENING IN THE FRONT THEREOF, A TRANSPARENT CLOSURE FOR SAID OPENING, A FLEXIBLE IMPREVIOUS DIAPHRAGM EXTENDING ABOUT THE PERIPHERY OF SAID OPENING WITH ITS OUTER PERIPHERY SECURED TO SAID HELMET ADJACENT SAID FACE OPENING AND WITH ITS INNER PERIPHERY DEFINING A FACE SEAL OPENING, AND A FLEXIBLE ENDLESS SEALING BAND SUPPORTED BY AND JOINED IN AIR-TIGHT RELATION TO SAID DIAPHRAGM AND EXTENDING AROUND SAID FACE SEAL OPENING FOR CONTACT AND CONFORMANCE WITH THE WEARER''S FACE, SAID SEALING BAND BEING PROVIDED WITH PASSAGES FOR CONDUCTING AIR THERETHROUGH IN CONTACT WITH THE WEARER''S FACE, AND MEANS INCLUDING AT LEAST ONE CONDUIT IN COMMUNICATION WITH THE PASSAGES IN SAID SEALING BAND FOR CONDUCTING AIR UNDER PRESSURE THERETO AND MEANS FOR SUPPLYING THE HELMET WEARER WITH A BREATHABLE GAS. 